1. Field of the Invention
The present invention relates to an aircraft control apparatus that controls a plurality of actuators that drive a device installed in an aircraft, and an aircraft control system that includes the aircraft control apparatus and the plurality of actuators.
2. Description of Related Art
As an aircraft control apparatus that controls a plurality of actuators that drive a device installed in an aircraft, U.S. Pat. No. 5,493,497 discloses an aircraft control apparatus that controls a plurality of actuators that drive control surfaces serving as the above-stated device. The aircraft control apparatus disclosed in U.S. Pat. No. 5,493,497 includes a plurality of control channels that control a plurality of actuators, each control channel including a power supply for supplying power. By including a plurality of control channels in this way, the aircraft control apparatus is intended to ensure the redundancy that enables the control surface to be driven and allows the operation of the control surface to be safely continued even if a failure has occurred in any of the control channels.
Also, each of the control channels of the above-described aircraft control apparatus includes a primary flight computer as an arithmetic processing unit. The primary flight computer receives, via an actuator control electronics serving as another electronic apparatus, a manipulation signal generated based on a manipulation of a wheel or the like performed by a pilot flying the aircraft. Based on the above-described manipulation signal, the primary flight computer calculates and generates an operation command signal for commanding and controlling the operation of the actuators that drive the control surfaces.
As stated above, by including a plurality of control channels, the above-described aircraft control apparatus is intended to ensure the redundancy that allows the operation of the control surfaces to be safely continued. However, if a failure has occurred in a primary flight computer, the control channel in which that primary flight computer is provided becomes also inoperable.
In the event of occurrence of a generic failure, that is, a failure that may occur commonly among the same pieces of software or hardware when primary flight computers having the same design are provided in a plurality of control channels, all of the control channels become inoperable. Therefore, although not disclosed in U.S. Pat. No. 5,493,497, for the aircraft control apparatus, a plurality of arithmetic processing portions having different designs need to be provided in the above-described primary flight computer of each of the control channels.
In this regard, the apparatus configuration of a primary flight control including a plurality of arithmetic processing portions having different designs is disclosed in FIG. 3 of the publication entitled “Challenges in Building Fault-Tolerant Flight Control System for a Civil Aircraft” published in “IAENG International Journal of Computer Science, 35:4, IJCS—35—4—07”. Note that the above publication has been released on the Internet at the following URL: “http://www.iaeng.org/IJCS/issues_v35/issue—4/IJCS—35—4—07.pdf”.
The above-described publication discloses the configuration of a primary flight control that is provided in each of a plurality of control channels that control a plurality of actuators. Also, the primary flight control receives a manipulation signal generated based on a manipulation performed by a pilot, and includes a plurality of arithmetic processing portions having different designs as arithmetic processing portions that generate an operation command signal for commanding and controlling the operation of the actuators. Specifically, the above-described publication discloses a configuration in which three arithmetic processing portions (“MICRO-PROCESSOR AMD 29050”, “MICRO-PROCESSOR MOTOROLA 68040”, “MICRO-PROCESSOR INTEL 80486”) having different designs manufactured by different manufacturers are provided in each primary control.